While many chairlifts, gondolas, ski lifts, trams and the like are permanently secured to the endless cable which conveys them, numerous aerial tranmway installations are constructed so that the personnel conveying chair or lift may be detached from the cable and reattached when and where desired. A typical detachable aerial tramway installation will include loading and unloading platforms proximate each end of the lift. As the chair or gondola approaches the loading and unloading platform, a mechanism engages the chair grip assembly and causes the grip to open and release the chair from the cable. The cable operates continuously, but the chair which has been released can be stopped for loading and unloading. Usually, the grip assembly and chair are lifted up off the moving cable by guide rollers and tracks, and the chair or gondola can be pushed by hand on the guide tracks from the unloading station around to a loading station. After loading the passengers into the chair or gondola, the operator advances the same along the track, which allows the grip to drop down onto the cable, and a grip attaching mechanism causes the grip to engage the cable on the fly so that chair or gondola again advances with and is carried by the cable.
Prior grip assemblies for detachably mounting chairs, gondolas and the like to moving cables have been found to have several disadvantages in their construction and operation. Primary among the disadvantages have been the problems associated with actuating, opening and closing, the gripping jaws of the assembly. This is usually accomplished by providing the grip assembly with a lever that can be pushed to open and to close the gripping jaws. In order to push the lever, however, the prior art grip assemblies have required rather cumbersome and complex support guides which can resist the moment induced about the longitudinal axis of the cable as a result of pushing on the actuating lever. Additionally, the displacement of the actuating lever will also cause a lateral displacement of the grip and cable unless the grip assembly is supported in the manner resisting the force on the lever. Since opening and closing of the cable grip usually takes place while both the cable and grip are moving, the grip assembly support problems at the loading and unloading terminals are substantial.